Bone Abstracts

We used atomic force microscopy (AFM) to study the morphology and development of mineralization-competent matrix vesicles (MVs) secreted by chondrocytes isolated from WT and Phospho1−/− mice in order to validate the role of PHOSPHO1 in MV mineralization. All MVs appeared as flattened globular features either individually dispersed or connected to a mat-like structure. The mat-like structure very closely resembled type-X collagen that has been de...

Bone metastasis (BM) is a dismal complication of cancer, occurring frequently in patients with advanced breast carcinoma. During metastatic progression, carcinoma cells harness osteoclast (OC) activity, promoting osteolysis. To adapt to hypoxia and/or to support proliferation, carcinoma cells adopt primarily glycolysis for energy production, therefore releasing lactic acid in the microenvironment through monocarboxylate transporter 4 (MCT4). Stressed by tumor cells, osteoblast...

Objectives: Osteogenesis imperfecta (OI) is a bone fragility disorder associated with reduced muscle size, dynamic muscle function and mobility. This paired randomised controlled pilot study assessed the effect of whole body vibration (WBV) training on bone density and geometry, muscle size and function, mobility, and balance in children with OI.Methods: Twenty-four children (5–16 years) with OI types 1,4 and limited mobility (defined as a Childhood...

Objectives: Low bone mineral density has been reported in children with beta thalassemia major, they also have increased propensity to fracture. We have studied DXA and pQCT variables in poorly chelated 3 to 18 year old thalassaemic patients and their relationship with fractures in this population.Methods: We studied 167, 3 to 18 year old children (Girls 72) with beta thalassemia major. Bone measurements were performed by GE iDXA (Lumbar Spine, Total bod...

Understanding normal patterns of bone growth is important for optimising bone health in children and reducing osteoporotic fractures in later life. Recently published guidelines for bone assessment in children state that to predict fractures a technique should identify children at risk of clinically significant fractures and that dual-energy absorptiometry (DXA) is the preferred method of assessment. Despite these guidelines there is still inconsistency and lack of consensus r...

Osteogenesis imperfecta (OI) classification has recently been broadened to include genes that primarily affect osteoblast differentiation. TMEM38B encodes TRIC-B, a ubiquitously expressed monovalent cation-specific channel protein involved in calcium release from the endoplasmic reticulum. How alterations in TMEM38B cause OI remains poorly understood and bone matrix characteristics in affected patients have not previously been described.<p class="abstext"...

Mechanical stimulation triggers periostin (Postn) expression in the periosteum and osteocytes (Oc), which downregulates Sost and activates β-catenin signaling. Hence the cortical bone response to loading is abolished in Postn−/− mice. Here we investigated the role of Oc β-catenin and its interaction with Postn on the bone biomechanical response. Postn−/− were bred with Oc-Ctnn−/− mice to generate Po...

Aim: The aim of the study was to investigate the relationship between gut hormones and bone re-modeling and intestinal growth by measuring meal stimulated changes in hormones and bone markers in blood samples collected from patients before and after gastric bypass (GBP).Methods: Eighteen patients (12 females and 6 males) were included in the study, approved by the Municipal Ethical Committee of Copenhagen. All subjects were studied before surgery (~2 wee...

Pparβ is crucial for muscle fatty acid oxidation. Pparβ−/− mice have reduced muscle strength, exercise performance, and also a decreased skeletal response to exercise. Here we investigate the influence of Pparβ on muscle and bone loss with aging, and its role on the bone biomechanical response to loading. Pparβ−/− and Pparβ+/+ mice were monitored at 1, 3 and 18...

Gene deletion or treatments with a cathepsin K (CatK) inhibitor in mature preclinical models result not only result in lower bone resorption but also in higher bone formation (BF) on both remodeling and modeling surfaces. Although increased production of clastokines and matrix-derived growth factors may explain the increased BF at remodeling surfaces, the mechanisms for greater BF at modeling surfaces, including the periosteum, remain unexplained. We hypothesized that the abse...